Internal-combustion engine



April r17, 1928.

P. o. sTRlBLlNG; JR INTERNAL coMBUsTI'oN ENGINE Filed Jan.1s, 1927 2 sneers-sneez 2 fill exhaust passages through the piston wall take the form of substantially rectangular openings provided between circumferential bands 34 and longitudinal bars 35. The shape of the openings may be Varied Within wide limits so long as there are provided longitudinal bearing surfaces such as the inner walls of bars 85, to prevent the rings of the lower head 18 from entering the openings and there are circumferential bands providing seats for packing rings 86. The several longitudinal bearing surfaces need not be in aXial alinement, and the circumferential bands need not be substantially transverse to the pistonaxis, but I believe such arrangements yto be preferable and therefore have illustrated inlet and exhaust passages, each of which comprises a plurality of polygonal slots, the slots of each group being yarranged in transverse and longitudinal alinement.

Vflic manner in which the engine operates will be understood. by those yfamiliar with this art, since the. invention does not reside in va new method of operation but in the specific structural details which cooperate to reduce the engine weight per horse power to a minimum. VThe engine illustrated in the drawings operates on a four-stroke cycle but suitable changes iii the valve timing mechanism and in the location yof the valve ports will permit operation on a two-stroke cycle.

The arrangement of the. ports in the piston skirt 19 and of the rings between adjacent pairsof transversely ali-ned ports is an important feature. The explosion pressure withinf the lower combustion chamber is transmitted through the ports in the piston to the inner sleeve of the 'valve mechanism. rlfhe packing rings however prevent the escape of gases along the. outer surface of the piston and thereby prevent the explosion pressure from reachingthe ports of the inner sleeve. i i

The two combustion chambers are so designed that they develop substantially equal power.` Thelocation ofthe spark plug 26 at the center ofthe lower head 18 and in longitudinal alineineiit with the upper spark plug 4 assists in securing uniformity in the operation of the/two combustion chambers.

It is tofbe understood that the invention is not limited to the particular embodiment which is shown in the drawings, since various changes may be made in the several parts, their relative size, shape and arrangementwithout departing from the spirit of my invention as set forth iii the following claims. l

I claim: 1. An internal combustion engine of the type comprising a cylinder having a head, a hollow piston movable in said cylinder forming a combustion chamber with one end thereof, a second head positioned within the skirt of said piston and cooperating therewith to form a second combustion chamber, said sleeve valves between the wall o f said cylinder and the skirt of said piston, characterized by the fact that the skirt of said piston is provided with sets of longitudinally spaced inlets and exhaust openings providing passages for the flow of gases into and out of said combustion chamber, and packing rings are arranged on said piston-beings. f l

2. The invention as set forth 4infclaiin 1, wherein each of said sets of openingsin the skirt of said piston is defined by circumferential bands and longitudinal bars, and packing rings located in seats formed in said circumferential bands."

'3. In an internal combustion engine, a cylinder having a head, a hollow piston nievable in said cylinder and forming a combustion chamber with one end thereof, asecond head positioned within the skirt ofthe piston and cooperating therewith to form a .second combustion chamber, sleevev valves between tween adjacent longitudinally spaced opensaid cylinder and said piston, packing rings on said heads and piston, and gas passages through said sleeves andpiston skirt', each of said passages comprising a plurality of openings of such dimensions that said packing rings cannot enter the saine. f

4. An internal combustion engine of the type including a hollow piston movable within a cylinder and between the cylinder head and a second head which is located within the'skirt of the piston, characterized by the fact that the inner head is provided with a threaded recess for receiving a sparkplug, the cylinder head and piston headliaving threaded apertures therethrough permitting the introduction of va spark plug, the piston head aperture being closed bya removable cap and the cylinder head aperture being adapted to receive a second spark.

5. A hollow piston for use in an engine of the type having a cylinder head and A`a second head mounted on the crank case, said piston having inlet and exhaust passagesthrough the skirt thereof, characterized by the fact that said passages each comprises a plurality of openings which are longitudinally spaced from each other, andpacking is provided on the skirt of said 'piston between adjacent ylongitudinally-spaced openings. j 6. A hollow piston for use in ane'ngine of the type having a cylinder head and a secondhead mounted on the crank case, said piston having inlet and exhaust passages through the skirt thereof, characterized by the fact that said, passages each comprises a plurality of openings arranged iii transverse and longitudinal alinement, and a packingring is provided on the piston skirtbetween adjacent sets. of transversely-ahmed 8. vThe invention as set orth'in claim 5,

openings. wherein the end of said piston is provided 7. The invention as set forth in Claim 5, with an `aperture permitting the passage 10 wherein said piston terminates in two diatherethrough of a spark plug, and a closurey metrically disposed extensions, and bearing therefor.

blocks are mounted on saidr extensions and vIn testimonj whereof, I aix my sinature.

adapted no receive a wrist pin. l PAUL o. sTRIBLIN, JR.- 

